Recombinant human TNFRII/CD120b Protein, His Tag, 50µg

Background
TNF RI (also known as the p60 or p55 TNFR) and TNF RII (the p75 or p80 TNFR) are two distinct type I transmembrane glycoproteins that bind TNF with highaffinity. Both RI and RII are prototypic members of the TNF receptor superfamily and have been designated TNFRSF1A and TNFRSF1B, respectively. Human TNF RII cDNA encodes a 461 amino acid (aa) residue precursor protein with a 22 aa putative signal peptide, a 235 aa extracellular domain, a 20 aa transmembrane domain and a 174 aa cytoplasmic domain. TNFRII is expressed in fetal brain. The protein is produced naturally as a soluble form (sTNFRII). The soluble receptor inhibits TNFα action by competing with cell surface receptors in binding TNFα, thereby blocking its biologic effects. TNFRII is strongly expressed at the cartilage–pannus junction, and plays a major role in a subset of families with multiple cases of rheumatoid arthritis (RA). Further, high plasma levels of sTNFRII were significantly associated with increased incidence of coronary heart disease, independent of established cardiovascular risk factors, and seems to be useful for monitoring the inflammatory activity of sarcoidosis. [1-4]

Source
Recombinant Human TNFR2 / CD120b / TNFRSF1B Protein, Leu 23 - Asp 257 (Accession # AAA36755) was produced in human 293 cells (HEK293).

Molecular Characterization
rhTNFRII, fused with a C-terminal 6×his tag, has a calculated MW of 26 kDa. The predicted N-terminus is Leu23. Protein migrates as 23-26 kDa in reduced SDS-PAGE due to glycosylation.

Endotoxin
Less than 1.0 EU endotoxin per μg rhTNFRII by the LAL method.

Purity
>95% purity as determined by SDS-PAGE of reduced rhTNFRII.

Formulation
Lyophilized from 0.22 μm filtered solution in PBS, pH 7.4. Normally Mannitol or Trehalose are added as protectants before lyophilization.

Reconstitution
See Certificate of Analysis for details of reconstitution instruction and specific concentration.

Storage
Avoid repeated freeze-thaw cycles.
No activity loss was observed after storage at:
In lyophilized state for 1 year (4°C-8°C); After reconstitution under sterile conditions for 1 month (4°C-8°C) or 3 months (-20°C to -70°C).

Bioactivity
Immobilized ActiveMax® Human TNF-alpha (Cat. No. TNA-H4211) at 5 μg/mL (100 μl/well) can bind Human TNFR2, His Tag (Cat. No. TN2-H5227). The EC50 of human TNFR2 is 647 ng/mL (QC tested).

Immobilized ActiveMax® Human TNF-beta (Cat. No. TNB-H5214) at 5 μg/mL (100 µl/well),can bind Human TNFR2, His Tag (Cat. No. TN2-H5227) with a linear range of 2-62 ng/mL (Routinely tested)

References

(1) Alicia SC, et al., 2005, Molecular and Cellular Biology, 25, No. 11: 4716-26.
(2) Ziegenhagen, MW., et al., 2000, Journal of Internal Medicine, 248(1): 33-41
(3) Iris Shai, et al., 2005, Diabetes Care, Vol. 28, No. 6: 1376-1382.
(4) MacEwan, D.J., 2002, Cell Signal. 14:477.